1/* 2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2016 SAP SE. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26#include "precompiled.hpp" 27#include "c1/c1_MacroAssembler.hpp" 28#include "c1/c1_Runtime1.hpp" 29#include "classfile/systemDictionary.hpp" 30#include "gc/shared/collectedHeap.hpp" 31#include "interpreter/interpreter.hpp" 32#include "oops/arrayOop.hpp" 33#include "oops/markOop.hpp" 34#include "runtime/basicLock.hpp" 35#include "runtime/biasedLocking.hpp" 36#include "runtime/os.hpp" 37#include "runtime/sharedRuntime.hpp" 38#include "runtime/stubRoutines.hpp" 39 40void C1_MacroAssembler::inline_cache_check(Register receiver, Register iCache) { 41 Label ic_miss, ic_hit; 42 verify_oop(receiver); 43 int klass_offset = oopDesc::klass_offset_in_bytes(); 44 45 if (!ImplicitNullChecks || MacroAssembler::needs_explicit_null_check(klass_offset)) { 46 if (VM_Version::has_CompareBranch()) { 47 z_cgij(receiver, 0, Assembler::bcondEqual, ic_miss); 48 } else { 49 z_ltgr(receiver, receiver); 50 z_bre(ic_miss); 51 } 52 } 53 54 compare_klass_ptr(iCache, klass_offset, receiver, false); 55 z_bre(ic_hit); 56 57 // If icache check fails, then jump to runtime routine. 58 // Note: RECEIVER must still contain the receiver! 59 load_const_optimized(Z_R1_scratch, AddressLiteral(SharedRuntime::get_ic_miss_stub())); 60 z_br(Z_R1_scratch); 61 align(CodeEntryAlignment); 62 bind(ic_hit); 63} 64 65void C1_MacroAssembler::explicit_null_check(Register base) { 66 ShouldNotCallThis(); // unused 67} 68 69void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes) { 70 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect"); 71 generate_stack_overflow_check(bang_size_in_bytes); 72 save_return_pc(); 73 push_frame(frame_size_in_bytes); // TODO: Must we add z_abi_160? 74} 75 76void C1_MacroAssembler::unverified_entry(Register receiver, Register ic_klass) { 77 ShouldNotCallThis(); // unused 78} 79 80void C1_MacroAssembler::verified_entry() { 81 if (C1Breakpoint) z_illtrap(0xC1); 82} 83 84void C1_MacroAssembler::lock_object(Register hdr, Register obj, Register disp_hdr, Label& slow_case) { 85 const int hdr_offset = oopDesc::mark_offset_in_bytes(); 86 assert_different_registers(hdr, obj, disp_hdr); 87 NearLabel done; 88 89 verify_oop(obj); 90 91 // Load object header. 92 z_lg(hdr, Address(obj, hdr_offset)); 93 94 // Save object being locked into the BasicObjectLock... 95 z_stg(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); 96 97 if (UseBiasedLocking) { 98 biased_locking_enter(obj, hdr, Z_R1_scratch, Z_R0_scratch, done, &slow_case); 99 } 100 101 // and mark it as unlocked. 102 z_oill(hdr, markOopDesc::unlocked_value); 103 // Save unlocked object header into the displaced header location on the stack. 104 z_stg(hdr, Address(disp_hdr, (intptr_t)0)); 105 // Test if object header is still the same (i.e. unlocked), and if so, store the 106 // displaced header address in the object header. If it is not the same, get the 107 // object header instead. 108 z_csg(hdr, disp_hdr, hdr_offset, obj); 109 // If the object header was the same, we're done. 110 if (PrintBiasedLockingStatistics) { 111 Unimplemented(); 112#if 0 113 cond_inc32(Assembler::equal, 114 ExternalAddress((address)BiasedLocking::fast_path_entry_count_addr())); 115#endif 116 } 117 branch_optimized(Assembler::bcondEqual, done); 118 // If the object header was not the same, it is now in the hdr register. 119 // => Test if it is a stack pointer into the same stack (recursive locking), i.e.: 120 // 121 // 1) (hdr & markOopDesc::lock_mask_in_place) == 0 122 // 2) rsp <= hdr 123 // 3) hdr <= rsp + page_size 124 // 125 // These 3 tests can be done by evaluating the following expression: 126 // 127 // (hdr - Z_SP) & (~(page_size-1) | markOopDesc::lock_mask_in_place) 128 // 129 // assuming both the stack pointer and page_size have their least 130 // significant 2 bits cleared and page_size is a power of 2 131 z_sgr(hdr, Z_SP); 132 133 load_const_optimized(Z_R0_scratch, (~(os::vm_page_size()-1) | markOopDesc::lock_mask_in_place)); 134 z_ngr(hdr, Z_R0_scratch); // AND sets CC (result eq/ne 0). 135 // For recursive locking, the result is zero. => Save it in the displaced header 136 // location (NULL in the displaced hdr location indicates recursive locking). 137 z_stg(hdr, Address(disp_hdr, (intptr_t)0)); 138 // Otherwise we don't care about the result and handle locking via runtime call. 139 branch_optimized(Assembler::bcondNotZero, slow_case); 140 // done 141 bind(done); 142} 143 144void C1_MacroAssembler::unlock_object(Register hdr, Register obj, Register disp_hdr, Label& slow_case) { 145 const int aligned_mask = BytesPerWord -1; 146 const int hdr_offset = oopDesc::mark_offset_in_bytes(); 147 assert_different_registers(hdr, obj, disp_hdr); 148 NearLabel done; 149 150 if (UseBiasedLocking) { 151 // Load object. 152 z_lg(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); 153 biased_locking_exit(obj, hdr, done); 154 } 155 156 // Load displaced header. 157 z_ltg(hdr, Address(disp_hdr, (intptr_t)0)); 158 // If the loaded hdr is NULL we had recursive locking, and we are done. 159 z_bre(done); 160 if (!UseBiasedLocking) { 161 // Load object. 162 z_lg(obj, Address(disp_hdr, BasicObjectLock::obj_offset_in_bytes())); 163 } 164 verify_oop(obj); 165 // Test if object header is pointing to the displaced header, and if so, restore 166 // the displaced header in the object. If the object header is not pointing to 167 // the displaced header, get the object header instead. 168 z_csg(disp_hdr, hdr, hdr_offset, obj); 169 // If the object header was not pointing to the displaced header, 170 // we do unlocking via runtime call. 171 branch_optimized(Assembler::bcondNotEqual, slow_case); 172 // done 173 bind(done); 174} 175 176void C1_MacroAssembler::try_allocate( 177 Register obj, // result: Pointer to object after successful allocation. 178 Register var_size_in_bytes, // Object size in bytes if unknown at compile time; invalid otherwise. 179 int con_size_in_bytes, // Object size in bytes if known at compile time. 180 Register t1, // Temp register: Must be global register for incr_allocated_bytes. 181 Label& slow_case // Continuation point if fast allocation fails. 182) { 183 if (UseTLAB) { 184 tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case); 185 } else { 186 // Allocation in shared Eden not implemented, because sapjvm allocation trace does not allow it. 187 z_brul(slow_case); 188 } 189} 190 191void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register Rzero, Register t1) { 192 assert_different_registers(obj, klass, len, t1, Rzero); 193 if (UseBiasedLocking && !len->is_valid()) { 194 assert_different_registers(obj, klass, len, t1); 195 z_lg(t1, Address(klass, Klass::prototype_header_offset())); 196 } else { 197 // This assumes that all prototype bits fit in an int32_t. 198 load_const_optimized(t1, (intx)markOopDesc::prototype()); 199 } 200 z_stg(t1, Address(obj, oopDesc::mark_offset_in_bytes())); 201 202 if (len->is_valid()) { 203 // Length will be in the klass gap, if one exists. 204 z_st(len, Address(obj, arrayOopDesc::length_offset_in_bytes())); 205 } else if (UseCompressedClassPointers) { 206 store_klass_gap(Rzero, obj); // Zero klass gap for compressed oops. 207 } 208 store_klass(klass, obj, t1); 209} 210 211void C1_MacroAssembler::initialize_body(Register objectFields, Register len_in_bytes, Register Rzero) { 212 Label done; 213 assert_different_registers(objectFields, len_in_bytes, Rzero); 214 215 // Initialize object fields. 216 // See documentation for MVCLE instruction!!! 217 assert(objectFields->encoding()%2==0, "objectFields must be an even register"); 218 assert(len_in_bytes->encoding() == (objectFields->encoding()+1), "objectFields and len_in_bytes must be a register pair"); 219 assert(Rzero->encoding()%2==1, "Rzero must be an odd register"); 220 221 // Use Rzero as src length, then mvcle will copy nothing 222 // and fill the object with the padding value 0. 223 move_long_ext(objectFields, as_Register(Rzero->encoding()-1), 0); 224 bind(done); 225} 226 227void C1_MacroAssembler::allocate_object( 228 Register obj, // Result: pointer to object after successful allocation. 229 Register t1, // temp register 230 Register t2, // temp register: Must be a global register for try_allocate. 231 int hdr_size, // object header size in words 232 int obj_size, // object size in words 233 Register klass, // object klass 234 Label& slow_case // Continuation point if fast allocation fails. 235) { 236 assert_different_registers(obj, t1, t2, klass); 237 238 // Allocate space and initialize header. 239 try_allocate(obj, noreg, obj_size * wordSize, t1, slow_case); 240 241 initialize_object(obj, klass, noreg, obj_size * HeapWordSize, t1, t2); 242} 243 244void C1_MacroAssembler::initialize_object( 245 Register obj, // result: Pointer to object after successful allocation. 246 Register klass, // object klass 247 Register var_size_in_bytes, // Object size in bytes if unknown at compile time; invalid otherwise. 248 int con_size_in_bytes, // Object size in bytes if known at compile time. 249 Register t1, // temp register 250 Register t2 // temp register 251 ) { 252 assert((con_size_in_bytes & MinObjAlignmentInBytesMask) == 0, 253 "con_size_in_bytes is not multiple of alignment"); 254 assert(var_size_in_bytes == noreg, "not implemented"); 255 const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize; 256 257 const Register Rzero = t2; 258 259 z_xgr(Rzero, Rzero); 260 initialize_header(obj, klass, noreg, Rzero, t1); 261 262 // Clear rest of allocated space. 263 const int threshold = 4 * BytesPerWord; 264 if (con_size_in_bytes <= threshold) { 265 // Use explicit null stores. 266 // code size = 6*n bytes (n = number of fields to clear) 267 for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += BytesPerWord) 268 z_stg(Rzero, Address(obj, i)); 269 } else { 270 // Code size generated by initialize_body() is 16. 271 Register object_fields = Z_R0_scratch; 272 Register len_in_bytes = Z_R1_scratch; 273 z_la(object_fields, hdr_size_in_bytes, obj); 274 load_const_optimized(len_in_bytes, con_size_in_bytes - hdr_size_in_bytes); 275 initialize_body(object_fields, len_in_bytes, Rzero); 276 } 277 278 // Dtrace support is unimplemented. 279 // if (CURRENT_ENV->dtrace_alloc_probes()) { 280 // assert(obj == rax, "must be"); 281 // call(RuntimeAddress(Runtime1::entry_for (Runtime1::dtrace_object_alloc_id))); 282 // } 283 284 verify_oop(obj); 285} 286 287void C1_MacroAssembler::allocate_array( 288 Register obj, // result: Pointer to array after successful allocation. 289 Register len, // array length 290 Register t1, // temp register 291 Register t2, // temp register 292 int hdr_size, // object header size in words 293 int elt_size, // element size in bytes 294 Register klass, // object klass 295 Label& slow_case // Continuation point if fast allocation fails. 296) { 297 assert_different_registers(obj, len, t1, t2, klass); 298 299 // Determine alignment mask. 300 assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work"); 301 302 // Check for negative or excessive length. 303 compareU64_and_branch(len, (int32_t)max_array_allocation_length, bcondHigh, slow_case); 304 305 // Compute array size. 306 // Note: If 0 <= len <= max_length, len*elt_size + header + alignment is 307 // smaller or equal to the largest integer. Also, since top is always 308 // aligned, we can do the alignment here instead of at the end address 309 // computation. 310 const Register arr_size = t2; 311 switch (elt_size) { 312 case 1: lgr_if_needed(arr_size, len); break; 313 case 2: z_sllg(arr_size, len, 1); break; 314 case 4: z_sllg(arr_size, len, 2); break; 315 case 8: z_sllg(arr_size, len, 3); break; 316 default: ShouldNotReachHere(); 317 } 318 add2reg(arr_size, hdr_size * wordSize + MinObjAlignmentInBytesMask); // Add space for header & alignment. 319 z_nill(arr_size, (~MinObjAlignmentInBytesMask) & 0xffff); // Align array size. 320 321 try_allocate(obj, arr_size, 0, t1, slow_case); 322 323 initialize_header(obj, klass, len, noreg, t1); 324 325 // Clear rest of allocated space. 326 Label done; 327 Register object_fields = t1; 328 Register Rzero = Z_R1_scratch; 329 z_aghi(arr_size, -(hdr_size * BytesPerWord)); 330 z_bre(done); // Jump if size of fields is zero. 331 z_la(object_fields, hdr_size * BytesPerWord, obj); 332 z_xgr(Rzero, Rzero); 333 initialize_body(object_fields, arr_size, Rzero); 334 bind(done); 335 336 // Dtrace support is unimplemented. 337 // if (CURRENT_ENV->dtrace_alloc_probes()) { 338 // assert(obj == rax, "must be"); 339 // call(RuntimeAddress(Runtime1::entry_for (Runtime1::dtrace_object_alloc_id))); 340 // } 341 342 verify_oop(obj); 343} 344 345 346#ifndef PRODUCT 347 348void C1_MacroAssembler::verify_stack_oop(int stack_offset) { 349 Unimplemented(); 350 // if (!VerifyOops) return; 351 // verify_oop_addr(Address(SP, stack_offset + STACK_BIAS)); 352} 353 354void C1_MacroAssembler::verify_not_null_oop(Register r) { 355 if (!VerifyOops) return; 356 NearLabel not_null; 357 compareU64_and_branch(r, (intptr_t)0, bcondNotEqual, not_null); 358 stop("non-null oop required"); 359 bind(not_null); 360 verify_oop(r); 361} 362 363void C1_MacroAssembler::invalidate_registers(Register preserve1, 364 Register preserve2, 365 Register preserve3) { 366 Register dead_value = noreg; 367 for (int i = 0; i < FrameMap::nof_cpu_regs; i++) { 368 Register r = as_Register(i); 369 if (r != preserve1 && r != preserve2 && r != preserve3 && r != Z_SP && r != Z_thread) { 370 if (dead_value == noreg) { 371 load_const_optimized(r, 0xc1dead); 372 dead_value = r; 373 } else { 374 z_lgr(r, dead_value); 375 } 376 } 377 } 378} 379 380#endif // !PRODUCT 381